1. how much to tip
2. how much interest is needed for a loan
3. figuring out how much sales tax
Answer:
the first four terms is 3, 0, -3, -6
The one that has green, blue and yellow
Answer:
a = 
Step-by-step explanation:
4a -16 = a - 15
both left and right -a
then
4a - 16 -a = a - 15 -a
then
4a -a -16 = a -a -15
then
3a -16 = -15
both left and right + 16
then
3a -16 + 16 = -15 + 16
then
3a = 1
both left and right ÷3
then
3a ÷ 3 =1 ÷ 3
then
a = 
X= 5y + 1
-2x + 9y = -1
-2(5y + 1) + 9y = -1
-10y - 2 + 9y = -1
-y - 2 = -1
-y = 1
y = -1
x + 5 = 1
x = -4
(-4, -1)